Question: Solve for $x$ and $y$ using elimination. ${-2x-4y = -48}$ ${-2x-3y = -39}$
Answer: We can eliminate $x$ by adding the equations together when the $x$ coefficients have opposite signs. Multiply the top equation by $-1$ ${2x+4y = 48}$ $-2x-3y = -39$ Add the top and bottom equations together. ${y = 9}$ Now that you know ${y = 9}$ , plug it back into $\thinspace {-2x-4y = -48}\thinspace$ to find $x$ ${-2x - 4}{(9)}{= -48}$ $-2x-36 = -48$ $-2x-36{+36} = -48{+36}$ $-2x = -12$ $\dfrac{-2x}{{-2}} = \dfrac{-12}{{-2}}$ ${x = 6}$ You can also plug ${y = 9}$ into $\thinspace {-2x-3y = -39}\thinspace$ and get the same answer for $x$ : ${-2x - 3}{(9)}{= -39}$ ${x = 6}$